1. Field
The present invention relates to data processing in digital electronic devices, and more particularly, to communication of messages between one or more application clients and one or more service entities.
2. Background
Modern computing devices such as personal computers, laptops, and personal digital assistants are often tethered to a data communication device such as a modem to enable the computing device to communicate over an interface such as IEEE 802.11, Code Division Multiple Access (CDMA), General Packet Radio Service (GPRS), or Universal Mobile Telecommunications System (UMTS). An operating system running on the computing device typically supports software application clients, such as a connection manager client, that use the communications capability provided by the data communication device to send and receive data. The data communication device itself may provide a number of services to software applications running on the computing device, such as a network access service for accessing a network system status, a wireless data service for transmitting and receiving data over a wireless link, and a device management service for accessing device identification and power level status.
At the physical layer, the communication between a computing device and the data communication device can take place over physical interconnect, such as serial buses including USB, RS-232, PCI and PCMCIA, or wireless interfaces including Bluetooth and IEEE 802.11. For upper-layer communication between application clients running on the computing device and services running on the data communication device, i.e., the client-service interface, protocols that have been utilized in the prior art include the AT command set specified for W-CDMA 3GPP terminals (see “AT command set for User Equipment, Release 1999, 3GPP TS 27.007 V3.13.0 (2003)) and CDMA 3GPP2 terminals (see “Data Service Options for Spread Specrum Systems: AT Command Processing and the Rm Interface,” 3GPP2 C.S0017-003-A), Remote Network Driver Interface Specification (RNDIS), and Universal Plug and Play (UPnP).
Recently, computing devices are supporting an increasing number of communications applications, while data communication devices are increasingly capable of supporting a multiple number of communications technologies. For example, a laptop computer may be running communications applications such as web browser, email, and calendar synchronization using a modem that supports Bluetooth, IEEE 802.11, and CDMA. This type of scenario has led to an increased need for certain client-service interface features not readily found in the prior art.